Planned dust collection system

[DennisCA]

Picture of the Mark II


Sides will be trimmed yet, should be 18" when done.

[phil (admin)]

Have u balanced it yet?

[DennisCA]

No point in doing that until I trim it I think, I'll have to rebalance it again then. I've ordered a bunch of ball bearings of the same bore diameter as the motor shaft  (28mm) so I can have the impeller turn on those in the circle cutting jig, otherwise I won't get a perfectly centered cut. So gotta wait for those to arrive. Then I can balance it. Building the enclosure instead meanwhile.

[phil (admin)]

Oh yeah good point.

Well I can't wait to hear how this one works.

I have high hopes.

[DennisCA]

Still waiting for the parts, checking my mailbox every day for the bearings, getting disappointed nearly every day too. Shoulda bought locally.

[DennisCA]

Well finally got the bearings. So I used my circle jig and made it round:


Then I balanced it on an M12 rod with bearings:


And it's back


Standing with the switch 10 meters away outside the shop I started it, probably a dozen times. Longest and last time was 5 seconds. Here it's in action, spinning down:


Seems to be holding up, and while it it's round and turns true in that way, though there is back and forth wobbling, especially on the front face, more so than the back face, which means it's not flat. I am not sure how big a deal it is, if I should set up a tool rest and correct it.

It's a really scary monster, the sound it makes makes me feel like a small bird getting sucked into a jet engine... And all the air it stirs up, jeezus good thing I am putting this in another room. I'd like it in the attic even, far away.

[phil (admin)]

It's alive!!!

Nice work, what a monster!

[DennisCA]

Thanks! Just got my new router (a bosch GMF 1600 CE, finally something to replace my €40 lidl-special) so I'll be working on a spiral cutting jig to get the walls just right. I figured out I don't wanna glue them together like Matthias Wandel did. I tried that and it quickly got annoying as heck, esp. since I don't have a miter saw or a miter gauge.

Also doing some other projects now so time, always so little time...

[DennisCA]

Not much has happened, real life interferes a lot. But I've decided to return the air back into the shop after all. So I will put in a filter bank after the separator and before the impeller. I am thinking a manifold that uses 3 or 4 smaller HEPA filters for shop vacs, or however many is needed for the the filters to not restrict air flow too much.

I read it's better to separate before, the impeller dislikes back pressure behind it more than an obstruction in front.

[phil (admin)]

I thought that if the separator was before the blower, that the filters have to be after it.

[DennisCA]

I have not heard of that, but in the woodgears dust collector, there's a filter manifold before the blower.

[DennisCA]

Finally got the top and bottom of the scroll housing routed. Now I need to make a hole in the bottom that's the size of the impeller. This so I can disassembled the scroll housing later without  much effort. I am copying Marius Hornbergers design in this.

Best way to cut this is with a router compass. I don't have one, but I have a fence and removing the fence part from the shafts is easy and requires no tools, so I made another attachment to work as a router compass:


Then setting it correctly:


Turn out I didn't set it correctly and made the hole a few millimeters too small, I thought about various solutions to enlarge it a bit but the best one turned out to be using a simple spokeshave and a kind of clamping jig, worked real well. I also routed a rabbet in the hole and I will rout a corresponding one in the insert plate.


Next up is to make the insert plate in question and mount it to the motor.

[DennisCA]

Surprised myself and got even further on this today:






I had to make a kind of complicated mounting method here in order to get the back of the impeller housing far back enough that the impeller wouldn't rub against the housing. The router c ompass jig has been exceptionally useful on its first day. Now I can start working on the walls for the scroll housing, I plan to use 4mm plywood, I have some that is very bendy in one direction.

[DennisCA]

Assembling the housing today, ran out of screws. Will have to pick it up tomorrow:




Pre-drilling every hole as not to split the plywood as well.

[phil (admin)]

Looks fantastic, amazing work!